LIS2DH - suspected noise

Hello there,
I had placed the LIS2DH on my board , and it seems to work fine.
using default setting and 10Hz sampling,
when i am putting the PCBA on a fixed position, and X axis raw data is unstable from - 128 to 128.
other axis seems to work fine - this is the raw data driven without any particular SW manipulation.
can someone advise why?